diff options
Diffstat (limited to 'drivers/acpi/osl.c')
| -rw-r--r-- | drivers/acpi/osl.c | 104 |
1 files changed, 25 insertions, 79 deletions
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c index 4be252145cb4..c8111424dcb8 100644 --- a/drivers/acpi/osl.c +++ b/drivers/acpi/osl.c @@ -35,7 +35,6 @@ #include <linux/interrupt.h> #include <linux/kmod.h> #include <linux/delay.h> -#include <linux/dmi.h> #include <linux/workqueue.h> #include <linux/nmi.h> #include <linux/acpi.h> @@ -97,54 +96,44 @@ static DEFINE_SPINLOCK(acpi_res_lock); static char osi_additional_string[OSI_STRING_LENGTH_MAX]; /* - * "Ode to _OSI(Linux)" + * The story of _OSI(Linux) * - * osi_linux -- Control response to BIOS _OSI(Linux) query. + * From pre-history through Linux-2.6.22, + * Linux responded TRUE upon a BIOS OSI(Linux) query. * - * As Linux evolves, the features that it supports change. - * So an OSI string such as "Linux" is not specific enough - * to be useful across multiple versions of Linux. It - * doesn't identify any particular feature, interface, - * or even any particular version of Linux... + * Unfortunately, reference BIOS writers got wind of this + * and put OSI(Linux) in their example code, quickly exposing + * this string as ill-conceived and opening the door to + * an un-bounded number of BIOS incompatibilities. * - * Unfortunately, Linux-2.6.22 and earlier responded "yes" - * to a BIOS _OSI(Linux) query. When - * a reference mobile BIOS started using it, its use - * started to spread to many vendor platforms. - * As it is not supportable, we need to halt that spread. + * For example, OSI(Linux) was used on resume to re-POST a + * video card on one system, because Linux at that time + * could not do a speedy restore in its native driver. + * But then upon gaining quick native restore capability, + * Linux has no way to tell the BIOS to skip the time-consuming + * POST -- putting Linux at a permanent performance disadvantage. + * On another system, the BIOS writer used OSI(Linux) + * to infer native OS support for IPMI! On other systems, + * OSI(Linux) simply got in the way of Linux claiming to + * be compatible with other operating systems, exposing + * BIOS issues such as skipped device initialization. * - * Today, most BIOS references to _OSI(Linux) are noise -- - * they have no functional effect and are just dead code - * carried over from the reference BIOS. - * - * The next most common case is that _OSI(Linux) harms Linux, - * usually by causing the BIOS to follow paths that are - * not tested during Windows validation. - * - * Finally, there is a short list of platforms - * where OSI(Linux) benefits Linux. - * - * In Linux-2.6.23, OSI(Linux) is first disabled by default. - * DMI is used to disable the dmesg warning about OSI(Linux) - * on platforms where it is known to have no effect. - * But a dmesg warning remains for systems where - * we do not know if OSI(Linux) is good or bad for the system. - * DMI is also used to enable OSI(Linux) for the machines - * that are known to need it. + * So "Linux" turned out to be a really poor chose of + * OSI string, and from Linux-2.6.23 onward we respond FALSE. * * BIOS writers should NOT query _OSI(Linux) on future systems. - * It will be ignored by default, and to get Linux to - * not ignore it will require a kernel source update to - * add a DMI entry, or a boot-time "acpi_osi=Linux" invocation. + * Linux will complain on the console when it sees it, and return FALSE. + * To get Linux to return TRUE for your system will require + * a kernel source update to add a DMI entry, + * or boot with "acpi_osi=Linux" */ -#define OSI_LINUX_ENABLE 0 static struct osi_linux { unsigned int enable:1; unsigned int dmi:1; unsigned int cmdline:1; unsigned int known:1; -} osi_linux = { OSI_LINUX_ENABLE, 0, 0, 0}; +} osi_linux = { 0, 0, 0, 0}; static void __init acpi_request_region (struct acpi_generic_address *addr, unsigned int length, char *desc) @@ -1296,34 +1285,6 @@ acpi_status acpi_os_release_object(acpi_cache_t * cache, void *object) return (AE_OK); } -/** - * acpi_dmi_dump - dump DMI slots needed for blacklist entry - * - * Returns 0 on success - */ -static int acpi_dmi_dump(void) -{ - - if (!dmi_available) - return -1; - - printk(KERN_NOTICE PREFIX "DMI System Vendor: %s\n", - dmi_get_system_info(DMI_SYS_VENDOR)); - printk(KERN_NOTICE PREFIX "DMI Product Name: %s\n", - dmi_get_system_info(DMI_PRODUCT_NAME)); - printk(KERN_NOTICE PREFIX "DMI Product Version: %s\n", - dmi_get_system_info(DMI_PRODUCT_VERSION)); - printk(KERN_NOTICE PREFIX "DMI Board Name: %s\n", - dmi_get_system_info(DMI_BOARD_NAME)); - printk(KERN_NOTICE PREFIX "DMI BIOS Vendor: %s\n", - dmi_get_system_info(DMI_BIOS_VENDOR)); - printk(KERN_NOTICE PREFIX "DMI BIOS Date: %s\n", - dmi_get_system_info(DMI_BIOS_DATE)); - - return 0; -} - - /****************************************************************************** * * FUNCTION: acpi_os_validate_interface @@ -1350,21 +1311,6 @@ acpi_os_validate_interface (char *interface) osi_linux.cmdline ? " via cmdline" : osi_linux.dmi ? " via DMI" : ""); - if (!osi_linux.dmi) { - if (acpi_dmi_dump()) - printk(KERN_NOTICE PREFIX - "[please extract dmidecode output]\n"); - printk(KERN_NOTICE PREFIX - "Please send DMI info above to " - "linux-acpi@vger.kernel.org\n"); - } - if (!osi_linux.known && !osi_linux.cmdline) { - printk(KERN_NOTICE PREFIX - "If \"acpi_osi=%sLinux\" works better, " - "please notify linux-acpi@vger.kernel.org\n", - osi_linux.enable ? "!" : ""); - } - if (osi_linux.enable) return AE_OK; } |